Used both (terra 8x25 and CL 8x25) side by side at same time at December 2022. And my opinion based on my two examples.
Terra better in:
1. Central Sharpness and Resolution (tested on grids of a brick walls, numbers on the cars, price tags in shops from large range). Terra more poison-sharp, but CL more milky-smoothed.
2. Glare Control.
3. Contrast and Colours saturation (Terra has a little warmer image, more colourful view. Overall tint white with a little-little pinkness. While CL more cold-greenish tint with pale colours).
4. A tiny more zoomy (at my eyes).
CL better in:
1. Body overall (with no dispute and doubt).
2. Brightness in the dark (by a 5-10% (max)).
3. Sharpness on sides and borders.
4. Ease of view with MOLCET-technigue.
I didnt test the VP 8x25, but i suppose that these are optically best 8x25 on market right now.
Also i tested side by side Leica UV BR 8x20 and Nikon HG L DCF 8x20, and with upper results i can summary tell next:
Body:
CL = UV => HGLDCF > Terra
Brightness (between cl and terra almost none):
CL => Terra > UV = HGLDCF
Glare control:
Terra >> CL = hgldcf = uv
Night view (cl only a bit-bit-bit brighter than terra; uv better than dcf only because of “ghost-glows” from lanterns on streets in dcf):
CL => terra > uv > hgldcf.
Ease of view with molcet-technics (in most cases i using it):
CL => Terra > Dcf > UV (leica pretty finicky).
FOV:
CL = Terra = Dcf >> UV
Edge to Edge sharpness:
CL => UV = DCF > Terra
Contrast (colour saturation. Leica has vivid colours):
UV > Terra > CL = Dcf
Central Resolution (between dcf and terra minimal):
Dcf => Terra > UV = CL
Overall Sharpness (resolution + contrast):
Terra => Dcf > UV => CL
Focus Depht:
Terra => CL = UV = DCF
TINTS, colour reproduction and PLACES overall:
1. Terra - white with a bit pinky tint (almost natural and neutral) with a bit-bit more brighter colours than real. For me it is “N1” 8x25 (before compared with VP 8x25) - none significant weaknesses and good in every aspect, especially in overall sharpness and colours. Low price for high optical quality. Real gem and diamond.
2. Hg L Dcf - yellow warm tint with colours with real brightness. For me it “N2” and definitely optically better than Leica uv 8x20 (more fov, better resolution, easier of view, better eyecups) - excellent resolution, good “edge-to-edge”, best eyecups, ease of view with “molcet” (for 8x20) - for price just a bit more expensive than terra. Weaknesses: ghost lights in darkness; non rubber on body; plastic upper part of the bridge. Another little diamond.
3. Swaro CL - cold-greenish tint with a more pale colours than real. Best quality of body, best brightness (not for much). But overall i dont think it worth its price, cuz for that money you can buy Terra+HgLDcf or VP 8x25 (that better overall). I had CL, sold it and saved my Terra and Dcf.
4. UV 8x20 - orange-reddish warm tint with vivid saturated colours. I didnt like these 8x20 almost at all: worst fov, ease of view and glare control (glare not by much, but anyway) - these cons killing my desire to use regularly, so thats why i sold it and instead of it saved my little beloved Dcf.
Everything that i wrote is just only opinion of mine and my eyes.
With respect…